Atlanta killer Mark Barton is not the first stressed-out day trader to commit suicide.

The Post has learned two New York City day traders killed themselves early last year.

Former colleagues said one of the suicides resulted from depression stemming from trading losses at JGM Trading, but the firm denied trading was the cause.

“One of the two was a really nice guy who was there for a while but he was having a tough time trading, and his suicide was definitely related to it,” said a trader who was at the desk with him.

Not so, said an exec.

“I got a call from the police that he left behind a note blaming a recent break-up with his girlfriend,” said George West, a managing member of JGM.

The other suicide victim, a former employee of market maker Spear, Leeds & Kellogg, had set up an account at Broadway Trading, a day-trading firm housed in the same Wall Street building as JGM, but an insider at the firm said he never used the account.

Still, the principals of the two associated firms were spooked by the suicides and decided to bring in a psychologist for grief and stress counseling.

Broadway Trading continues to pay for psychological counseling for any of its customers.

Yesterday it sent this note, penned by CEO Marc Friedfertig, to all customers: “I would like to remind all of you of Broadway’s long-standing policy to encourage any of you who is troubled by the daily challenges, that we offer counseling through the Village Institute.”

Friedfertig told The Post that because the counseling visits are anonymous, he does not know how many of his traders go – but admitted he suspected it was too few, considering the stresses of the job.

In May, the Massachusetts branch of All-Tech – the same firm where Barton traded – paid $50,000 in fines and reimbursed $228,000 in customers’ funds to settle a complaint from the Massachusetts Secretary of the Commonwealth’s office.

At the time, All-Tech chief Harvey Houtkin blamed the problem on one “bad apple.”